In a variety of settings, it may be useful to ensure precise delivery of intravenous fluids. One mode of intravenous fluid delivery is the gravity infusion set. One problem with using a gravity infusion set is the challenge of (a) establishing an initial flow rate and (b) monitoring the flow rate over time.
A device for establishing and monitoring flow rate may be in the form of an all-in-one device having an infrared light source and photodiode, microprocessor, battery, and display. Such a device may also attach directly to the drip chamber and may provide continuous monitoring of a flow rate during a gravity infusion. An infrared light source and a photodiode may be mounted on opposing sides of the drip chamber so that the beam crosses through the path of a falling drip. The microprocessor may periodically measure the light sensed by the photodiode and, by sensing the change in detected light, can detect that a drop has fallen. By measuring the elapsed time between detected drops, the microprocessor can measure and then display a drop rate.
Two factors which contribute to successful monitoring of a gravity infusion via optical beam drop detection are (a) proper alignment of a sensing element on the drip chamber body and (b) secure attachment of a monitoring device to the drip chamber. If either of these factors are compromised, incomplete or inaccurate monitoring can result, as the beam may not be properly aligned to sense each falling drop, or the device might slip out of alignment. An all-in-one device may be subject to user misalignment on the drip chamber. In addition, design considerations for an all-in-one device may be complicated by aspects employed to securely attach the device to a wide variety of user-supplied drip chambers, which may vary significantly in geometry and materials of construction.